New Study Reveals Boredom, Not Just Stress, Drives Hair-Pulling Disorder

Hippocrates wrote about it in 410 BCE. Aristotle catalogued it among human vices around 350 years later. Yet for all that history, trichotillomania—the compulsive pulling of hair from scalp, eyebrows, eyelashes, or skin—remains poorly understood. We have long assumed it was a response to stress, a way the body copes with anxiety or emotional pain. A new study from Heidelberg University Hospital suggests that assumption may be incomplete, even misleading.

The condition affects between one and two percent of Americans, striking men and women equally. It often travels alongside other mental-health struggles: anxiety, depression, PTSD, OCD, ADHD. The damage is real—hair loss, visible scarring, social withdrawal, shame. Clinically, it belongs to a category called body-focused repetitive behaviors, and for decades the prevailing theory held that people pull to regulate their emotions, to find relief from the unbearable weight of feeling too much.

But the evidence for this emotional-regulation model has always been messy. Researchers noticed that people pull their hair while distracted, while watching television, while lost in thought—moments when no particular emotional crisis is happening. To understand what actually drives the urge in real time, the Heidelberg team recruited 61 adults with trichotillomania and followed them for ten days using a method called ecological momentary assessment. Rather than asking people to remember their day in an evening journal entry, the researchers sent seven prompts daily between 8 a.m. and 10 p.m., asking participants to report their emotional state right then, how strong their urge to pull felt, and whether they had pulled since the last check-in. Participants could also log episodes as they happened.

The data was granular: 2,557 momentary assessments, 702 documented hair-pulling episodes. When the researchers analyzed the patterns, something unexpected emerged. Yes, negative emotions—anxiety, anger, sadness, guilt, nervousness—were associated with stronger urges. But they were far less predictive of actual pulling than the urges themselves were. Stronger urges at one assessment reliably predicted pulling at that same moment or the next one. Previous pulling episodes made future episodes more likely, suggesting the behavior builds momentum through a day. Emotional states, by contrast, were much weaker predictors.

One state stood out above all others: boredom. Boredom predicted hair-pulling episodes both immediately and at the next assessment. Tiredness also predicted stronger urges, though it did not directly predict pulling. The pattern suggested something the researchers articulated carefully in their paper, published in Comprehensive Psychiatry: hair pulling may not be primarily about managing distress. It may be about managing stimulation itself—or the lack of it. Under-arousal, low energy, the restless ache of having nothing to do and nothing to feel—these states of under-stimulation appeared to create vulnerability for the urge to pull.

This reframes the problem. If trichotillomania were simply an emotional-regulation strategy, we would expect it to spike during moments of high stress or sadness. Instead, the data suggested that boredom and low stimulation were equally or more important drivers. The researchers noted that repetitive behaviors may serve a self-stimulatory function, a way of generating internal sensation when the world feels flat. Negative emotions can certainly be part of the urge experience, they cautioned, but they may not be the primary cause.

The study has limits. The sample was small and skewed female. Participants had to be motivated enough to complete an intensive ten-day protocol—a selection bias. Assessments could be four hours apart, meaning rapid emotional shifts might have gone unrecorded. The researchers also acknowledged that trichotillomania may not work the same way in everyone; there may be subtypes, different pathways to the same behavior.

Still, the findings suggest a shift in how we think about treatment. If boredom and under-arousal matter as much as emotional distress, then interventions focused solely on anxiety management or emotional coping may miss half the picture. The more useful question becomes not just why someone pulls, but what happens in the space between the urge and the action—the role of boredom, sensory experience, environmental cues, and awareness itself. For people living with this condition, that distinction could matter enormously.